Chapter 3 pre-test
1amu= 1.660 x 10-27kg; Avagadro’s number=6.022 x 1023;
mp=1.007276amu; mn=1.008665amu;
me=0.000548 amu;
1.
What is an alpha particle? What is it’s charge? If it had electrons what would it be?
Alpha particles are Helium atoms nuclei. (He atom without the electrons). 2+, 2e-
2.
What is deuterium? Deuterium is an isotope of hydrogen. 21H
3.
How many protons, electrons and neutrons are there in an atom of neon-20? p=e=n=10
4.
Complete the following table.
# electrons
#protons
#neutrons
#nucleons
Silicon-28
14
14
14
28
Silicon-29
14
14
15
29
Silicon-30
14
14
16
30
5.
All isotopes of silicon share what number in common? Atomic number
6.
What is the atomic number and mass number for helium-3? Atomic number = 2, Mass
number = 3
7.
Write the nuclear symbol for uranium-238. 23892U
8.
Give the nuclear symbol and hyphenated name for the element with 94 electrons and
145 neutrons. 23994Pu, Pu-239
9.
If oxygen-16 gains a neutron what does it become? Oxygen-17
10.
If
11.
How did they define 1amu? 1/12 of the mass of one C-12 atom
126
53I
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added a proton and four neutrons what would it be? (Nuclear symbol) 13154Xe
Chapter 3 pre-test
12. How is a mole defined?
6.022 x 1023 particles
13.
What is the mass in grams in 3.2 moles of lithium? How many atoms?
22.2 g Li, 1.97 x 1024 atoms
14.
If we you have 49.000 gms of lithium, how many moles would you have?
7.0605 mol Li
15.
How many moles of platinum are there in 0.100 gms? (Platinum molar
mass=195.08amu) 5.31 x 10-4
16.
What is the mass in grams of 1x10-9 moles of platinum?
2 x 10-7
17.
What is the average atomic mass of uranium given the following table?
% natural abundance
Atomic mass
Uranium-234
0.005
234.040
Uranium-235
0.720
235.043
Uranium-238
99.275
238.051
18.
What is the molar mass of carbon dioxide, CO2 (carbon molar mass=12.011, oxygen
molar mass=15.999)?
238.029 g/mol
19.
If you have 30.00 gms of carbon and you completely convert it to CO2, how much
oxygen did this take in grams?
44.008 g O
20.
If you have a half a mole of electrons, what would be the mass in grams?
0.002743 g
21.
If you have 1.466 x 1022 atoms of platinum, what is the mass in grams? 4.749 g Pt
22.
Review the three laws and three scientists. Look in book
23.
Ion problem Look in book
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